140 THE SCOTTISH NATURALIST 



ON THE OCCURRENCE OF STENOMALUS 

 MUSCARUM (LINN.) IN COMPANY WITH 

 HIBERNATING FLIES. 



By James Waterston, B.D., B.Sc, Imperial Bureau of 

 Entomology, London. 



In December 191 5 the late Mr G. Meade- Waldo handed me a 

 few living Chalcids which he had just taken " from windows " 

 at Hever, Kent. These specimens, evidently Pteromalini, 

 were staged and put aside to be worked out later. More 

 recently — January-February of this year (1916) — through 

 the kindness of Dr C. J. Gahan, Keeper in the Department 

 of Entomology, British Museum, South Kensington, London, 

 who was at the time conducting an inquiry into the com- 

 position of the swarms of flies occasionally found hibernating 

 in houses, two additional lots of Chalcids from English 

 localities were submitted to me.^ After considering these 

 and the Kentish material I came to the conclusion that all 

 belonged to the species named by Walker, Pteromalus 

 thessalus, a synonym of the older Ichneumon niuscarum, 

 Linn., for which Thomson erected Stetiomalns in 1878. 



On seeing Mr Grimshaw's note on p. 114 of the May 

 number of this magazine, it occurred to me that the Chalcids 

 incidentally mentioned there might be worth examining. 

 Although Mr Grimshaw could not, unfortunately, supply any 

 of the specimens mentioned in his note, he was able to send 

 some Chalcids from a similar assemblage of flies found 

 at Largo, in Fife, which form the subject of the preceding 

 article. These also proved to be Stenomalus inuscanim 

 (Linn.). A few notes on the above occurrences may be 

 given. 



I. S. muscarum (Linn.) appears to be a more or less 

 constant member of the mainly Dipterous association of 

 insects found wintering in houses. 



^ The following details have been received regarding one of these 

 consignments: "On shutter, Swindon, Gloucestershire, January 1916 

 (coll. Rev. E. D. Goddard)." The accompanying flies were PoHema 

 rudis and Lwwophora septemnotata. 



